First Step: Preheat and Prepare Preheat your oven to 400°F (200°C). Prepare a 9×13-inch baking dish by greasing it lightly with oil or nonstick spray to prevent sticking during baking.

Second Step: Cook Pasta Bring a large pot of salted water to a rolling boil. Add 1 pound of penne pasta (or preferred small pasta shapes) and cook for 8-10 minutes until slightly undercooked this prevents the pasta from becoming mushy after baking. Drain well and set aside.

Third Step: Brown the Beef Mixture In a large skillet or Dutch oven, heat 1 tablespoon olive oil over medium-high heat. Add the chopped onion and lean ground beef. Break the meat into small pieces with a spatula and cook for 8-10 minutes until the beef is browned and the onion is tender. Drain off excess fat if necessary.

Fourth Step: Add Seasoning and Sauce Stir in minced garlic and sauté briefly until fragrant, about 30 seconds. Add 1.5 cups marinara sauce (or tomato paste mixture) along with salt and freshly ground black pepper to taste. Optionally, add a splash of Worcestershire sauce or beef broth to deepen the flavor. Let simmer gently for 5 minutes to meld flavors together.

Fifth Step: Combine Pasta and Beef Sauce Mix the drained pasta into the beef sauce in the skillet or transfer both to your baking dish and combine thoroughly but gently. The mixture should be coated evenly to distribute flavor throughout.

Sixth Step: Add Cheese and Bake Sprinkle 1.5 cups of shredded sharp cheddar cheese evenly on top of the pasta and beef mixture. Place the baking dish in the preheated oven and bake uncovered for 10 minutes, or until the cheese is melted and bubbly. For a golden, crispy top, broil for 2-3 minutes, watching carefully to prevent burning.

Final Step: Rest and Serve Remove the casserole from the oven and let it rest for about 5 minutes before serving. This helps the casserole set, making it easier to portion. Garnish with fresh parsley or scallions if desired for a bit of color and freshness.